Method and apparatus for applying adhesives to a lead frame

ABSTRACT

A method for applying a viscous material to a lead frame element. A method of the invention includes positioning the lead frame facing downward and bringing the lead fingers into contact with a pool of adhesive material. The contact of the lead fingers to the adhesive material results in a portion of the lead fingers receiving a portion of the adhesive material from the pool of adhesive material. The gravitational forces on the adhesive material on the downward facing lead frame maintain the shape and boundary definition of the adhesive material.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a continuation of application Ser. No.09/405,943, filed Sep. 27, 1999, pending, which is a continuation ofapplication Ser. No. 08/906,673, filed Aug. 5, 1997, now U.S. Pat. No.6,013,535, issued Jan. 11, 2000.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to applying viscous materials tolead fingers of a lead frame, such as an adhesive material for theattachment of the lead fingers to a semiconductor die. Moreparticularly, the present invention relates to applying adhesivematerial to the lead fingers by contacting the lead fingers with a poolof adhesive material.

[0004] 2. State of the Art

[0005] Higher performance, lower cost, increased miniaturization ofsemiconductor components, and greater packaging density of integratedcircuits are goals of the computer industry. One way to reduce theoverall cost of a semiconductor component is to reduce the manufacturingcost of that component. Lower manufacturing costs can be achievedthrough faster production and/or reduction in the amount of materialsused in fabricating the semiconductor component.

[0006] One area where faster production and reduction in material usagecan be achieved is in the area of lead frame attachment to semiconductordice. U.S. Pat. No. 5,286,679 issued Feb. 15, 1994 to Farnworth et al.(“the ′679 patent”), assigned to the assignee of the present inventionand hereby incorporated herein by reference, teaches attaching leads toa semiconductor device with adhesive material in a “lead-over-chip”(“LOC”) configuration. The ′679 patent teaches applying a patternedthermoplastic or thermoset adhesive layer to a semiconductor wafer. Theadhesive layer is patterned to keep the “streets” on the semiconductorwafer clear of adhesive for saw cutting and to keep the wire bondingpads on the individual dice clear of adhesive for wire bonding.Patterning of the adhesive layer is generally accomplished by hot orcold screen/stencil printing or dispensing by roll-on. Following theprinting and baking of the adhesive layer on the semiconductor wafer,the individual dice are singulated from the semiconductor wafer. Duringpackaging, each adhesive coated die is attached to lead fingers of alead frame by heating the adhesive layer and pressing the lead fingersonto the adhesive. If the adhesive layer is formed of a thermosetmaterial, a separate oven cure is required. Furthermore, the adhesivelayer may be formulated to function as an additionalpassivating/insulating layer or alpha barrier for protecting thepackaged die.

[0007] Although the teaching of the ′679 patent is an effective methodfor attaching leads in a LOC configuration, it is difficult to achievean adequate profile on the adhesive such that there is sufficient areaon the top of the adhesive to attach the lead fingers. The processdisclosed in the ′679 patent is illustrated in FIGS. 14-20. FIG. 14illustrates a side, crosssectional view of a semiconductor substrate 302with a bond pad 304, wherein a stencil or a screen print template 306has been placed over the semiconductor substrate 302, generally asilicon wafer. The stencil or screen print template 306 is patterned toclear the area around the bond pads 304 and to clear street areas 308for saw cutting (i.e., for singulating the substrate into individualdice). An adhesive material 310 is applied to the stencil or screenprint template 306, as shown in FIG. 15. Ideally, when the stencil orscreen print template 306 is removed, adhesive prints 312 are formedwith vertical sidewalls 314 and a planar upper surface 316, as shown inFIG. 16. However, since the adhesive material 310 must have sufficientlylow viscosity to flow and fill the stencil or screen print template 306,as well as allow for the removal of the stencil or screen print template306 without the adhesive material 310 sticking thereto, the adhesivematerial 310 of the adhesive prints 312 will spread, sag, or flowlaterally under the force of gravity after the removal of the stencil orscreen print template 306, as shown in FIG. 17. This post-applicationflow of adhesive material 310 can potentially cover all or a portion ofthe bond pads 304 or interfere with the singulating of the semiconductorwafer by flowing into the street areas 308.

[0008] Furthermore, and of even greater potential consequence than bondpad or street interference is the effect that the lateral flow or spreadof adhesive material 310 has on the adhesive material upper surface 316.As shown in FIG. 18, the adhesive material upper surface 316 is thecontact area for lead fingers 318 of a lead frame 320. Thegravity-induced flow of the adhesive material 310 causes the oncerelatively well-defined edges 322 of the adhesive material to curve,resulting in a loss of surface area 324 (ideal shape shown in shadow)for the lead fingers 318 to attach. This loss of surface area 324 isparticularly problematical for the adhesive material upper surface 316at the longitudinal ends 326 thereof. At the adhesive materiallongitudinal ends 326, the adhesive material flows in three directions(to both sides as well as longitudinally), causing a severe curvature328, as shown in FIGS. 19 and 20. The longitudinal ends of the adhesiveprint on patch flow in a 180° flow front, resulting in blurring of theprint boundaries into a curved perimeter. This curvature 328 results incomplete or near complete loss of effective surface area on the adhesivematerial upper surface 316 for adhering the outermost lead fingerclosest to the adhesive material longitudinal end 326 (lead finger 330).This results in what is known as a “dangling lead.” Since the leadfinger 330 is not adequately attached to the adhesive materiallongitudinal end 326, the lead finger 330 will move or bounce when awire bonding apparatus (not shown) attempts to attach a bond wire (notshown) between the lead finger 330 and its respective bond pad 304(shown from the side in FIG. 20). This movement can cause inadequatebonding or non-bonding between the bond wire and the lead finger 330,resulting in the failure of the component due to a defective electricalconnection.

[0009] LOC attachment can also be achieved by attaching adhesive tape,preferably insulative, to an active surface of a semiconductor die, thenattaching lead fingers to the insulative tape. As shown in FIG. 21, twostrips of adhesive tape 410 and 410′ are attached to an active surface412 of a semiconductor die 404. The two adhesive tape strips 410, 410′run parallel to and on opposing sides of a row of bond pads 406. Leadfingers 402, 402′ are then attached to the two adhesive tape strips 410,410′, respectively. The lead fingers 402, 402′ are then electricallyattached to the bond pads 406 with bond wires 408. Although this methodis effective in attaching the lead fingers 402, 402′ to thesemiconductor die 404, this method is less cost effective than usingadhesive since the cost of adhesive tape is higher than the cost ofadhesive material. The higher cost of the adhesive tape is a result ofthe manufacturing and placement steps which are required with adhesivetapes. The individual tape segments are generally cut from a larger tapesheet. This cutting requires precision punches with extremely sharp andaccurate edges. These precision punches are expensive and they wear outover time. Furthermore, there is always waste between the segments whichare punched out, resulting in high scrap cost. Moreover, once punch outis complete, the tape segments are placed on a carrier film fortransport to the die-attach site. Thus, there are problems withplacement, alignment, and attachment with film carriers, plus the costof the film carrier itself.

[0010] LOC attachment can further be achieved by placing adhesivematerial on the lead fingers of the lead frame rather than on thesemiconductor substrate. As shown in FIG. 22, the adhesive material 502may be spray applied on an attachment surface 504 of lead fingers 506.However, the viscous nature of the adhesive material 502 results in theadhesive material 502 flowing down the sides 508 of the lead finger 506and collecting on the reverse, bond wire surface 510 of the lead finger506, as shown in FIG. 23. The adhesive material 502, which collects andcures on the bond wire surface 510, interferes with subsequent wirebonding, which, in turn, can result in a failure of the semiconductorcomponent. The flow of adhesive material 502 for the attachment surface504 to the bond wire surface 510 can be exacerbated if the lead fingers506 are formed by a stamping process rather than by etching, the otherwidely employed alternative. The stamping process leaves a slightcurvature 512 to edges 514 of at least one surface of the lead finger506, as shown in FIG. 24. If an edge curvature 512 is proximate the leadfinger attachment surface 504, the edge curvature 512 results in lessresistance (i.e., less surface tension) to the flow of the adhesivematerial 502. This, of course, results in the potential for a greateramount of adhesive material 502 to flow to the bond wire surface 510.

[0011] Furthermore, present methods of adhesive material application ona surface (whether the semiconductor die or the lead fingers) tend towaste adhesive material. For example, spray application loses a greatdeal of adhesive material because not all of the sprayed adhesivematerial attaches to the target surface. As another example, thepatterning of an adhesive layer on a semiconductor die, such asdescribed in the ′679 patent, results in a substantial area of theadhesive pattern not being utilized to attach leads.

[0012] Thus, it can be appreciated that it would be advantageous todevelop a method and apparatus for rapidly applying an adhesive materialto a lead finger with little waste of adhesive material.

SUMMARY OF THE INVENTION

[0013] The present invention relates to a method for applying a viscousmaterial, such as an adhesive material, to lead fingers of a lead framewherein surfaces of the lead fingers which receive the viscous materialface downward to contact a pool of adhesive material. Preferably, theviscous material is an adhesive material which cures with the lead framein this downward facing position. The advantages of placing viscousmaterial, such as an adhesive material, in a downward facing positionare described in U.S. patent application Ser. No. 08/709,182 by TongbiJiang and Syed S. Ahmad filed Sep. 6, 1996, assigned to the assignee ofthe present invention and hereby incorporated herein by reference.

[0014] Rather than gravitational forces causing the viscous material toflow and expand as when on top of the lead frame, the gravitationalforces on the inverted lead frame maintain the Do shape and boundarydefinition of the viscous material.

[0015] It is, of course, understood that the viscous material must becompatible with the lead finger material so as to adhere thereto andmust not be of such a low viscosity that it drips when the lead fingersare removed from contact with the viscous material pool. Preferably, theviscous materials have viscosities between about 1000 cps and 500,000cps.

[0016] Furthermore, with regard to drying or curing an adhesivematerial, the lead frame need only be inverted until the viscousadhesive material has stabilized sufficiently to maintain its shape andboundary definition. Depending on the particular viscous adhesivematerial used, the minimum inversion time could be the time required tocure the outer surfaces of the viscous adhesive material such that afilm is formed which contains the as yet uncured viscous adhesivematerial therein, or the minimum inversion time could be the timerequired to completely dry or cure the viscous adhesive material.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0017] While the specification concludes with claims particularlypointing out and distinctly claiming that which is regarded as thepresent invention, the advantages of this invention can be more readilyascertained from the following description of the invention when read inconjunction with the accompanying drawings in which:

[0018]FIG. 1 is a top plan view of a typical lead frame strip;

[0019]FIGS. 2 and 3 are schematic representations of one process of thepresent invention;

[0020]FIG. 4 is a schematic representation of an alternate process ofthe present invention;

[0021] FIGS. 5-7 are side views of a process of contacting lead fingerswith an adhesive material according to a method of the presentinvention;

[0022]FIG. 8 is a side cross-sectional view of a lead finger afteradhesive material attachment according to a method of the presentinvention;

[0023]FIG. 9 is a cross-sectional view of a lead finger along line 9-9of FIG. 8 after adhesive material attachment;

[0024]FIG. 10 is a cross-sectional view of a lead finger after adhesivematerial attachment, wherein the adhesive material exhibits excessivewetting of the lead finger;

[0025]FIG. 11 is a schematic representation of a mechanical mechanismfor maintaining the height of an exposed surface of an adhesivematerial;

[0026]FIG. 12 is a schematic representation of a height detection andcontrol loop for maintaining the height of an exposed surface of anadhesive material;

[0027]FIG. 13 is a schematic representation of another multiple adhesivematerial attachment process of the present invention;

[0028] FIGS. 14-20 are side cross-sectional views of a prior arttechnique of forming adhesive areas on a substrate for LOC attachment;

[0029]FIG. 21 is a top view of a prior art technique of LOC attachmentusing adhesive tape;

[0030] FIGS. 22-24 are side cross-sectional views of a prior arttechnique of forming adhesive areas on lead fingers for LOC attachment;

[0031]FIG. 25 is a plate-type reservoir design according to the presentinvention; and

[0032]FIG. 26 is a spillway-type reservoir design according to thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

[0033]FIG. 1 illustrates a portion of an exemplary lead frame strip 100.It should be understood that the figures presented in conjunction withthis description are not meant to be actual views of any particularportion of an actual semiconducting device or component, but are merelyidealized representations which are employed to more clearly and fullydepict the process of the invention than would otherwise be possible.Individual lead frames 102, each including a plurality of lead fingers104, are formed in a long, thin strip of conductive material 106, suchas copper, copper alloy, or the like. The lead frames 102 are generallyformed by a stamping process or an etching process. The lead frames 102are formed side-by-side along the conductive material strip 106 whereinthe conductive material strip 106 includes a plurality of indexing holes107, 107′ on opposing lengthwise edges 109, 109′, respectively, of theconductive material strip 106. The indexing holes 107, 107′ are used tomove the lead frame strip 100 and align the lead frames 102 throughout aprocess of attaching the lead frames 102 to semiconductor dice (notshown).

[0034]FIGS. 2 and 3 illustrate a schematic of one process of the presentinvention. Elements common to FIGS. 1, 2, and 3 retain the same numericdesignation. The lead frame strip 100, such as illustrated in FIG. 1, isfed from a source 108, such as a spool, to an adhesive reservoir 110. Asshown in FIG. 3, the lead fingers 104 (not shown) of the lead frame 102(not shown) are aligned over the adhesive reservoir 110 and the leadframe strip 100 is biased downward in direction 112, such as byhydraulic, pneumatic, or electrically-powered biasing mechanisms 116, tocontact an adhesive material 114. The adhesive material 114 may be anyviscous adhesive material including, but not limited to, thermoplastics,thermoset resins, flowable pastes, and B-stage adhesive materials.Preferred adhesive materials 114 include cyanate ester, bismaleimide,epoxy, and polyimide.

[0035]FIG. 4 illustrates a schematic of another process of the presentinvention which is similar to the process of FIGS. 2 and 3. Elementscommon to FIGS. 2 and 3 and FIG. 4 retain the same numeric designation.The only difference between the processes of FIGS. 2 and 3, and FIG. 4is that the process of FIG. 4 employs an elevator mechanism 117 to movethe adhesive reservoir 110 in an upward direction 120 to contact thelead fingers 104 rather than biasing the lead frame strip 100 downwardto the adhesive reservoir 110.

[0036] It is, of course, understood that the biasing and elevatormechanisms 116 and 117 shown in FIGS. 2-4 are not required to bring theadhesive material 114 into contact with the lead fingers 104. Instead,the lead fingers 104 may be brought into close proximity to the adhesivereservoir 110 and additional adhesive material 114 may be delivered by apump to the adhesive reservoir 110 to raise the level of the adhesivematerial 114 to contact the lead fingers 104, or to provide a movingwave or surge of adhesive material traveling across the reservoir 110.

[0037] FIGS. 5-7 illustrate side views of the lead fingers 104 beingbrought into contact with the adhesive material 114 and being retractedtherefrom. Elements common to FIGS. 2-4 and FIGS. 5-7 retain the samenumeric designation. As shown in FIG. 5, the lead fingers 104 arepositioned over the adhesive reservoir 110. The adhesive reservoir 110has the adhesive material 114 extending above edges 111 of the adhesivereservoir 110. Due to the forces of adhesion and surface tensioninherent in the adhesive material 114, an exposed surface 122 of theadhesive material 114 will form a meniscus, or convex-shapedconfiguration, above the reservoir edges em. 111.

[0038] As shown in FIG. 6, the lead fingers 104 are lowered onto orproximate the exposed surface 122 of the adhesive material 114. When abottom surface 124 of the lead fingers 104 comes in contact with theexposed surface 122 of the adhesive material 114, the adhesive material114 wets out across the bottom surface 124 of the lead finger 104. Asshown in FIG. 7, when the lead fingers 104 are retracted from theadhesive material 114, the cohesion of the adhesive material 114 withthe lead fingers 104 pulls some of the adhesive material 114 from thebulk of the adhesive material 114 to form an adhesive film 126 on thebottom surface 124 of the lead finger 104. The thickness of the adhesivefilm 126 can range from 0.1 to 15 mils, depending on the viscosity ofthe adhesive material 114. Changing the shape of the lead finger 104,changing the rheology of the adhesive material 114, pre-coating the leadfinger 104 with a surfactant, such as NMP, or placing a solvent in theadhesive material 114 to improve wetting and/or adding adhesionpromoters, such as silane, siloxane, or polyimide siloxane, to theadhesive material 114 will also change the thickness and/or pattern ofthe adhesive film 126. It is, of course, understood that the adhesivematerial 114 must be capable of adhering to the lead fingers 104 andmust not be of such a low viscosity that it drips when the lead fingers104 are removed from contact with the exposed surface 122 of theadhesive material 114.

[0039]FIG. 8 is a side cross-sectional view of a lead finger 104 afteradhesive material 114 application. FIG. 9 is a cross-sectional view ofthe lead finger 104 of FIG. 8 along line 9-9. As shown in FIGS. 8 and 9,by only contacting the bottom surface 124 of the lead finger 104 withthe exposed surface 122 of the adhesive material 114, the adhesivematerial 114 will not wet sides 128 of the lead finger 104 and, ofcourse, will not collect on a bond wire surface 130 of a lead finger 104(the bond wire surface 130 is the lead finger surface where a bond wireis subsequently attached during further processing). Since the adhesivematerial 114 does not collect on the bond wire surface 130, there willbe no adhesive material 114 to interfere with a subsequent wire bondingstep subsequent to LOC attachment of the lead fingers 104 to an activesurface of a semiconductor die.

[0040] Referring back to FIG. 5, the adhesive reservoir 110 can beshaped such that the exposed surface 122 of the adhesive material 114 isin a precise location. When the lead fingers 104 contact the exposedsurface 122 of the adhesive material 114, the adhesive material 114attaches to only specific, desired portions of the lead fingers 104.

[0041] It is very important that the exposed surface 122 be as level aspossible. If the exposed surface 122 is not level, the lead fingers 104may extend too deeply into the adhesive material 114. When this occurs,the adhesive material 114 may wet the lead finger sides 128 and may evenwet the lead finger bond wire surface 130, as shown in FIG. 10. If theadhesive material 114 wets the bond wire surface 130, the adhesivematerial 114 may interfere with a subsequent wire bonding stepsubsequent to LOC attachment of the lead fingers 104 to an activesurface of a semiconductor die, as mentioned above.

[0042] Numerous techniques may be used to keep the exposed surface 122of the adhesive material 114 level. It is, of course, understood thatexposed surface 122 extends from the adhesive reservoir 110 due to aslight excess of adhesive material 114 within the adhesive reservoir110. As shown in FIG. 11, the adhesive material 114 is pumped to theadhesive reservoir 110 from an adhesive material source (not shown) by apump 132. A desired exposed surface height 134 of exposed surface 122can be achieved by feeding an excess of adhesive material 114 into theadhesive reservoir 110 such that an initial exposed surface height 136is higher than the desired exposed surface height 134. A meteringmechanism, such as wiper 138, can be utilized to meter the adhesivematerial 114 from the initial exposed surface height 136 to the desiredexposed surface height 134.

[0043] Moreover, a desired exposed surface height 134 of exposed surface122 can be achieved by feeding an excess of adhesive material 114 intothe adhesive reservoir 110 such that an initial exposed surface height136 is higher than the desired exposed surface height 134. The adhesivematerial 114 is then drawn back (e.g., by vacuum), which results in aflattening of the exposed surface 122.

[0044] Furthermore, a variety of feed back and feed forward controlschemes may be used to control the desired exposed surface height 134 ofthe exposed surface 122. One such control scheme is shown in FIG. 12.Elements common to FIG. 11 and FIG. 12 retain the same numericdesignations. A height detection mechanism, shown as a transmitter 140and a receiver 142, is used to determine the height of the exposedsurface 122. A control signal 144 triggers the pump 132 to stop or avalve (not shown) to shut when the desired exposed surface height 134 isachieved. The transmitter 140 and receiver 142 may be a light(preferably a laser) transmitter and receiver. When a light beam (notshown) from the transmitter 140 is altered by the exposed surface 122,the receiver 142 detects the discontinuation of light transmission andgenerates the control signal 144. Additionally, the transmitter 140 andreceiver 142 may be an ultrasonic transmitter and receiver. When anultrasonic sound wave (not shown) from the transmitter 140 is altered bythe exposed surface 122, the receiver 142 detects the change in transittime or phase shifts of the ultrasonic sound wave and generates thecontrol signal 144.

[0045] It is, of course, understood that precise control of the leadframe position relative to the exposed surface 122 is required toaccurately control the depth to which the lead fingers 104 are pressedinto the adhesive material 114.

[0046] It is also understood that multiple reservoirs 110 could beconfigured as shown in FIG. 13. With such a configuration, the adhesivematerial 114 can be applied to the lead fingers 104 of multiple leadframes 102 simultaneously. The group of lead frames 102 is then indexedforward and another group is presented to the multiple reservoirs 110for coating.

[0047] Once the adhesive material 114 has been applied to the leadfingers 104, the lead frame strip 100 may, optionally, be fed to acuring oven 118, shown in FIGS. 2, 3, 4, and 13, to set the adhesivematerial 114. A semiconductor die (not shown) then can be attached to alead frame 102 and adhesive film 126 by known LOC attach methods.

[0048] It is, of course, understood that the present invention is notlimited to the above detailed description. The structures coated are notlimited to lead frames and can include TAB structures and the like. Thelead frames may not be limited to delivery in strips, but can bedelivered individually or in sheets. The viscous material can be appliedto a structure under at least a partially-evacuated chamber such thatlower-viscosity materials could be used and still form a meniscuswherein the viscous material applied to the structure would be at leastpartially dried or cured prior to removal from the chamber.

[0049] Furthermore, the present invention is not limited to onlyapplying a viscous material to lead fingers, but it is also contemplatedthat the viscous material may be applied to bus bars, die attachpaddles, or other structures of a lead frame, as well as dipping anysemiconductor component which requires a coating of a viscous material.Additionally, the viscous material is not limited to adhesives, but mayinclude various viscous materials for a variety of applications. Onesuch application includes applying a polyimide film to a lead frame inorder to eliminate the need for Kapton™ tape.

[0050] Moreover, the reservoir may be any structure which exposes aviscous material pool and may be one of a variety of designs, as shownin FIGS. 25-26. FIG. 25 illustrates a plate-type reservoir 150 in whicha very thin layer of viscous material 152 is delivered across plate 154from an inlet 156 to an opposing outlet 158. FIG. 26 illustrates areservoir 160 with a curved-edge spillway 162. The viscous material 164is pumped into a chamber 166 and over the spillway 162 at a constantrate. This results in a self-limiting viscous material height 168. Thelead fingers of a lead frame are contacted with the viscous material 164over the spillway 162 where the viscous material 164 would inherently,due to its viscosity, form a raised area 170 over the spillway 162 intoa spill chamber 172.

[0051] Having thus described in detail preferred embodiments of thepresent invention, it is to be understood that the invention defined bythe appended claims is not to be limited by particular details set forthin the above description as many apparent variations thereof arepossible without departing from the spirit or scope thereof.

What is claimed is:
 1. A method for applying viscous material to atleast one semiconductor component, said method comprising: providing aviscous material pool containing viscous material, said viscous materialpool shaped such that an exposed surface of the viscous material islocated in a precise location and including at least one upward facingopening, said opening exposing at least said exposed surface of saidviscous material; aligning at least one semiconductor component oversaid viscous material pool; and wetting a specific location of said atleast one semiconductor component with viscous material.
 2. The methodaccording to claim 1, wherein said providing a viscous material poolcontaining viscous material comprises providing a viscous material poolcontaining adhesive or polyimide.
 3. The method according to claim 2,wherein said providing a viscous material pool containing viscousmaterial comprises providing a viscous material pool containing adhesiveselected from the group consisting of thermoplastics, thermoset resins,flowable pastes, and B-stage adhesive materials.
 4. The method accordingto claim 1, wherein said aligning at least one semiconductor componentcomprises placing at least one of a lead finger, bus bars, and dieattach paddle above said viscous material pool.
 5. The method accordingto claim 1, wherein said aligning comprises aligning said at least onesemiconductor component above said at least one opening.
 6. The methodaccording to claim 1, wherein said wetting comprises biasing said atleast one semiconductor component downward proximate the viscousmaterial in said viscous material pool such that said specific locationof said at least one semiconductor component contacts said exposedsurface of said viscous material.
 7. The method according to claim 6,wherein said biasing comprises providing at least one of a hydraulicbiasing mechanism, pneumatic biasing mechanism, and electrically-poweredbiasing mechanism configured to place said at least one semiconductorcomponent proximate said viscous material.
 8. The method according toclaim 1, wherein said wetting comprising raising said viscous materialpool upward proximate said at least one semiconductor component suchthat said specific location of said at least one semiconductor componentcontacts said exposed surface of said viscous material.
 9. The methodaccording to claim 1, further comprising pumping said viscous materialinto said viscous material pool.
 10. The method according to claim 1,wherein said wetting comprises pumping said viscous material to a heightabove said viscous material pool sufficient to contact said specificlocation of said at least one semiconductor component.
 11. The methodaccording to claim 10, wherein said pumping comprises creating a movingwave of viscous material traveling across said viscous material pool.12. The method according to claim 1, wherein said wetting comprisesapplying a layer of viscous material having a thickness between 0.1 to15 mils on said specific location of said at least one semiconductorcomponent.
 13. The method according to claim 1, further comprisingcoating said surface of the at least semiconductor component with asurfactant prior to wetting said specific location of said surface withsaid viscous material.
 14. The method according to claim 1, furthercomprising adding an adhesion promoter to said viscous material, whereinsaid adhesion promoter is selected from the group consisting of silane,siloxane, and polyimide siloxane.
 15. The method according to claim 1,further comprising leveling said exposed surface of viscous materialprior to wetting said at least one semiconductor component.
 16. Themethod according to claim 15, wherein said leveling comprises: providingsaid viscous material to said viscous material pool such that saidexposed surface of said viscous material reaches an initial exposedsurface height higher than a desired exposed surface height; andflattening said initial exposed surface height to the desired exposedsurface height.
 17. The method according to claim 16, wherein saidflattening comprises metering said initial exposed surface height with awiper.
 18. The method according to claim 16, wherein said providing saidviscous material comprises pumping said viscous material into saidviscous material pool.
 19. The method according to claim 16, whereinsaid flattening said initial exposed surface height comprises drawingback said viscous material to flatten said exposed surface of saidviscous material.
 20. The method according to claim 1, furthercomprising controlling the height of said exposed surface of viscousmaterial using a detection mechanism.
 21. The method according to claim20, wherein said controlling the height of said exposed surface ofviscous material comprises: delivering said viscous material to saidviscous material pool; providing a detection mechanism comprising atransmitter, a receiver, and a control signal; utilizing saidtransmitter and said receiver to determine the height of the exposedsurface; providing said control signal to control delivery of viscousmaterial to said viscous material pool.
 22. The method according toclaim 21, wherein said providing said control signal comprisestriggering a pump to stop delivering viscous material to said viscousmaterial pool when a desired height of said exposed surface is achieved.23. The method according to claim 21, wherein said providing saidcontrol signal comprises triggering a valve to shut to preventadditional viscous material from entering said viscous material pool.24. The method according to claim 20, wherein said providing a detectionmechanism comprises providing a laser transmitter, wherein a light beamfrom said transmitter is altered by the exposed surface and the receiverdetects the alteration of said light beam and then generates a controlsignal.
 25. The method according to claim 20, wherein said providing adetection mechanism comprises providing an ultrasonic transmitter,wherein an ultrasonic sound wave from the transmitter is altered by theexposed surface and the receiver detects the alteration of theultrasonic sound wave and then generates the control signal.
 26. Themethod according to claim 1, wherein said providing a viscous materialpool comprises providing said viscous material pool including multiplereservoirs housing said viscous material.
 27. The method according toclaim 1, further comprising feeding said at least one semiconductorcomponent through a curing oven to set the viscous material.
 28. Themethod according to claim 27, further comprising attaching saidsemiconductor component to a semiconductor die.
 29. The method accordingto claim 1, wherein said wetting comprises applying said viscousmaterial to a precise location on said at least one semiconductorcomponent under at least a partially-evacuated chamber.
 30. The methodaccording to claim 1, wherein said providing a viscous material poolcomprises providing said viscous material pool including an inlet, andoutlet and a plate-type reservoir, wherein said at least one upwardfacing opening exposes said plate-type reservoir and wherein saidviscous material flows from said inlet across a plate and into saidoutlet such that a thin layer of said viscous material is deliveredacross said plate.
 31. The method according to claim 1, wherein saidproviding a viscous material pool comprises providing said viscousmaterial pool including a first chamber, a curved-edge spillway and aspill chamber, wherein said at least one opening exposes saidcurved-edge spillway.
 32. The method according to claim 31, furthercomprising pumping said viscous material into said first chamber andover said curved-edge spillway at a constant rate.
 33. The methodaccording to claim 32, wherein said wetting comprising contacting aspecific portion of said at least one semiconductor component with theviscous material over the curved-edge spillway.
 34. A method forapplying viscous material to at least one semiconductor component, saidmethod comprising: providing a viscous material pool including at leastone reservoir containing viscous material, said viscous material pooldefined by at least one peripheral edge having a height and configuredsuch that an exposed surface of the viscous material is located in aprecise location, said viscous material pool including at least oneupward facing opening exposing at least said exposed surface of saidviscous material, said exposed surface of viscous material having aheight that extends above said height of said at least one peripheraledge; leveling the exposed surface of said viscous material; and coatingonly a specific portion of a surface of at least one semiconductorcomponent with said viscous material.
 35. The method according to claim34, wherein said providing a viscous material pool including at leastone reservoir containing viscous material comprises providing a viscousmaterial pool containing adhesive or polyimide.
 36. The method accordingto claim 35, said providing a viscous material pool containing viscousmaterial comprises providing a viscous material pool containing adhesiveselected from the group consisting of thermoplastics, thermoset resins,flowable pastes, and Bstage adhesive materials.
 37. The method accordingto claim 34, wherein said coating only a specific portion of a surfaceof at least one semiconductor component comprises applying said viscousmaterial to at least one of a lead finger, bus bars, and die attachpaddle.
 38. The method according to claim 34, wherein said coating onlya specific portion of a surface of at least one semiconductor componentcomprises aligning said at least one semiconductor component over saidat least one opening such that said exposed surface contacts only saidspecific portion of said surface of at least one semiconductorcomponent.
 39. The method according to claim 34, wherein said coatingcomprises biasing said at least one semiconductor component downwardproximate the viscous material in said viscous material pool such thatsaid exposed surface of said viscous material contacts said specificportion of said surface of at least one semiconductor component.
 40. Themethod according to claim 39, wherein said biasing comprises providingat least one of a hydraulic biasing mechanism, pneumatic biasingmechanism, and electrically-powered biasing mechanism configured toplace said at least one semiconductor component proximate said viscousmaterial pool.
 41. The method according to claim 34, wherein saidcoating comprising raising said viscous material pool upward proximatesaid at least one semiconductor component such that said exposed surfaceof said viscous material contacts said specific portion of said surfaceof at least one semiconductor component.
 42. The method according toclaim 34, further comprising pumping said viscous material into saidviscous material pool.
 43. The method according to claim 34, whereinsaid coating comprises pumping said viscous material to a height abovesaid viscous material pool, wherein said height of said viscous materialis sufficient to contact only said specific portion of said at least onesemiconductor component.
 44. The method according to claim 43, whereinsaid pumping comprises creating a moving wave of viscous materialtraveling across said viscous material pool.
 45. The method according toclaim 34, wherein said coating comprises applying a layer of viscousmaterial having a thickness between 0.1 to 15 mils to said specificlocation of said at least one semiconductor component.
 46. The methodaccording to claim 34, further comprising coating said surface of the atleast semiconductor component with a surfactant prior to coating saidspecific portion of said surface with said viscous material.
 47. Themethod according to claim 34, further comprising adding an adhesionpromoter to said viscous material, wherein said adhesion promoter isselected from the group consisting of silane, siloxane, and polyimidesiloxane.
 48. The method according to claim 34, wherein said levelingcomprises: providing said viscous material to said viscous material poolsuch that said exposed surface of said viscous material reaches aninitial exposed surface height higher than a desired exposed surfaceheight; and flattening said initial exposed surface height to thedesired exposed surface height.
 49. The method according to claim 48,wherein said flattening said initial exposed surface height comprisesmetering said initial exposed surface height with a wiper.
 50. Themethod according to claim 48, wherein said providing said viscousmaterial comprises pumping said viscous material into said viscousmaterial pool.
 51. The method according to claim 48, wherein saidflattening said initial exposed surface height comprises drawing backsaid viscous material to flatten said exposed surface of said viscousmaterial.
 52. The method according to claim 48, further comprisingcontrolling the height of said exposed surface of viscous material usinga detection mechanism.
 53. The method according to claim 52, whereinsaid controlling the height of said exposed surface of viscous materialcomprises: delivering viscous material to said viscous material pool;providing a detection mechanism comprising a transmitter, a receiver,and a control signal; utilizing said transmitter and said receiver todetermine the height of the exposed surface; providing said controlsignal to control delivery of said viscous material.
 54. The methodaccording to claim 53, wherein said providing said control signalcomprises triggering a pump to stop delivering said viscous material tosaid viscous material pool when a desired height of said viscousmaterial is achieved.
 55. The method according to claim 53, wherein saidproviding said control signal comprises triggering a valve to shut toprevent additional viscous material from entering said viscous materialpool.
 56. The method according to claim 52, wherein said providing adetection mechanism comprises providing a laser transmitter, wherein alight beam from said transmitter is altered by the exposed surface andthe receiver detects the alteration of said light beam and thengenerates a control signal.
 57. The method according to claim 52,wherein said providing a detection mechanism comprises providing anultrasonic transmitter, wherein an ultrasonic sound wave from thetransmitter is altered by the exposed surface and the receiver detectsthe alteration of said ultrasonic sound wave and then generates thecontrol signal.
 58. The method according to claim 34, further comprisingfeeding said at least one semiconductor component through a curing ovento set the viscous material.
 59. The method according to claim 58,further comprising attaching said semiconductor component to asemiconductor die.
 60. The method according to claim 34, wherein saidcoating comprises applying said viscous material to said specificlocation on said at least one semiconductor component under at least apartially-evacuated chamber.
 61. The method according to claim 34,wherein said providing a viscous material pool comprises providing saidviscous material pool including an inlet, and outlet and a plate-typereservoir, wherein said at least one upward facing opening exposes saidplate-type reservoir and wherein said viscous material flows from saidinlet across a plate and into said outlet such that a thin layer of saidviscous material is delivered across said plate.
 62. The methodaccording to claim 34, wherein said providing a viscous material poolcomprises providing said viscous material pool including a firstchamber, a curved-edge spillway and a spill chamber, wherein said atleast one upward facing opening exposes said curved-edge pillway. 63.The method according to claim 62, further comprising pumping saidviscous material into said first chamber and over said curved-edgespillway at a constant rate.
 64. The method according to claim 63,wherein said wetting comprising contacting a specific portion of said atleast one semiconductor component with the viscous material over thecurved-edge spillway.
 65. The method according to claim 34, wherein saidcoating only a specific portion of a surface of at least onesemiconductor component comprises coating a bottom surface of at leastone lead finger with said viscous material.